Draft-regulator.



A. W. WALKER.

DRAFT REGULATOR.

APPLIUATION FILED ooT.1s, 1912.

Patented Aug. 11, 19M..

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UNITED sTATEs ARTHUR W. WALKER,y 0F MALDEN, MASSACHUSETTS.

DRAFT-REGULATOR.

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Specification of Letters Patent.

PATENT rateatea aug.` ii, ieri.

Application filed October 18, 1912. SerialvNo. 726,417.

5 State of Massachusetts, have invented new and useful Improvements-in Draft-Regula- This invention relates to improvements in .draft regulators.

More particularly it relates to regulators for controlling the combustion in a furnace of any sort, for example, the furnace in a stove or range, or in the heating plant Aof a building, whether operating through the medium of hot air, steam, or hot water.

` Such furnaces as now constructed cornmonly have an ash it underthe grate, provided with a door or removal of ashes, thel door having a draft slide for 'admission of air directly to the grate. They also have a duct leading from the fire-box to the chimney flue, to discharge smoke and gaseous products of combustion. For controlling the rate of combustion a check draft7 is 5 sometimes provided, admitting. more or less air directly to the fiue, thus diminishing the capacityor suction ofthe flue for products of combustion.

lt is an important feature of the present invention that these three elements, infiow of air to the grate to support combustion, outflow of products of combustion, and inflow of air directly to the flue for checking itssuction may all becontrolled directly by 35 a single moving part or adjustment. n

"s Another feature is that the invention prof'vides means for controlling definitely the amount of air having access to the grate to support combustion, and permits theash-pit tight.

There are also other features and advantages incidental to the invention, which will appear from the disclosure herein made.

In the accompanying'drawings: Figure 1 is a side elevation of a furnace, of a type used for heating a residence; Fig. 2 is a perspective view of a detail, enlarged, showing a form modified in 011e respect; and Figs. 3, 4 and 5 are side elevations 1n medial vertical section, on the larger scale, showing in dctail the regulator of F ig. 1 or Fig. .2 in threev different positions.

In the drawings, which represent one manner of applying the invention to a hot air furnace of a typenow in extensivo use tors, of which the following is a specification. l

door to be eliminated if desired, or made air,

for heating residences and buildings, 10 rep.- resents the Ere-box of the furnace, 11 the grate, 12 the ash-pit under it and 13 the door to the ash-pit.

and .smoke pipe that receives the discharge and conducts it to the chimney fiue, this ipe being'herein for. brevity called the ue.7 It will be understood that the products of combustion may pass either directly or indirectly from the re-boxto the according to any suitable or desired arrangement of passage within the heater, and also that thel door 13 of the as -pit may have the usual draft slide for admitting air, though this is made unnecessary by the pres ent invention, the air to support combustion being introduced and controlled bythe novel means now to be described.

' 16 is an inlet for fresh air arranged adj acent to the discharge4 pipe 14 from the firebox, and to the air entrance. to flue 15 and -also adjacent to the entrance to a duct 17, herein called the draft duct, by which air to support combustion'is conducted to the ggrate. As illustrated, this' inlet 16 is placed atl the levelof the'dome or top of the fire Q'box, on the back side of the apparatus, where Ithe pipe. for the discharge of smoke and igases Vfrom the fire-box issues from the apparatus and joins the flue.; and the draft `duct is a pipe leading thence downward on the back side and into the apparatus terminating in the ash-pit 1 2. But this might be arranged differently if desired', and the draft duct may, for example, be within the easing, or formed within the castings, or may be otherwise arranged, as by going within the combustion chamber and downward through `the grate to the ash-pit. Air entering at 16 may also go upward into the flue 15 to check the draft on the furnace.

` The numeral 18 indicates a damper which, in the form illustrated in the drawing, is hinged on a pivot pin 19, and can control vall four passages, viz, from the smoke discharge to the flue, from the air inlet to the flue, the air inlet alone, and the opening from the air inlet to the 'draft duct. To do this it is capable of being set in the various positions illustrated in Figs. 3, 4 and 5, and in various intermediate positions. The damper has a lower wing or yane 18 adapted to close, or open to varying degrees, the entrance to the draft duct 17; an upper vane 1S adapted l .f co 14 1s the discharge duct from the firebox,

15 the pipe sometimes known as the discharge 111 to switchlheliue either to a connection with air inlet 1G, or with the smoke discharge 14, or to bot-h, in an intermediate degrec; and a vane 18 which may be con- Fig. 3 to that of Fig. 4, so that this movee ment does not open the check draft connection from inlet 16 to the flue, although it does diminish the opening of draft duct 17. The plate 18 Whichcloses the inlet 16 when in its extreme downward position, is set so that its lower surface retreats gradually toward the center, from the line traveled by the tip of the vane 18". As a consefuence it is not necessary that the lower en of this plate get past the wall 21 before air can enter the flue, but an openin is formed as soon as its leading edge, w ich is the tip of vane 18, passes, gradually increasing with further movement toward the position Aof Fig. 5. The surface 21 is gen,- erated as a portion of a cylinder concentric with the pivot 19 about which the vane 18" swings; and the face ofthe plate 18'l may be of any design which produces the desiredl increase of opening from '16 into 15. While this increase is occurring, draft duct 17 and also the discharge lpipe 14 are being gradually closed. A handle 20 may be arranged 4outside of the chamber or box 21 in which the damper is set, to control its position' and this handle may in turn be controlled either manually or automatically. Thus, 1n

l Fig. 1, the presence of a thermostatic or other type of controller is indicated'by a wire 22, which may be assumed to descend as the temperature increases, letting the weight 20 draw the handle and thusturn the damper around to the left toward the posit-ion of Fig. 5. If automa-tic control be not used, any suitable means may be employed for maintaining the damper fixed in its desired position, such as the friction incidental to the parts, or a simple rack 23 i' pivoted to the handle and resting on a pin 24 as indicated in Fig. 2.

In the usual operation of a furnace embodying the invention, all the air which is to support combustionl enters through the draft duct 17, thus enabling the usualash-pit door to be omitted, or, ifnot, to be made airtight, and enabling perfect control. of the amount of air. Movement of handle 20 diminishes the size of the discharge opening for the.

ticularly their servants ingly the pull of the chimney flue, by admitting air thereto. As the same movement of handle 20 diminishes the size of draft duct, the combustion is reduced more effectually` than if it remained open, in which case the power that the fire itself has to create a draft might continue the combustion for some time on a larger scale than desired.

Hitherto the adjustmentl of the openings through the ash-pit door forthe admission of air has had to be made according to the judgment of the person charged with the care of the'furnace. Housekeepers, and parare rarelyskilled as combustion engineers. The slide draft fdr, admitting air is frequently shut too much to permit getting the full power of the furnace when that is wanted, or open too much to get combustion -at an economical rate, when that is wanted.l There is no way to measure the area openings, cracks, etc., that let air through the ash-pit door,v even if one knew precisely what area of opening is desirable. It is in fact customary for householders to' set the slide draft, smoke damper and check draft independently of each other, making considerable changes with one, without changing the others. f Y

The present invention, bythe construction. described or suitable modifications of it, enables the various dampers in the passages for cont-rolling combustion to be designed bycompetent combustion engineers when the K The *unskilled* housekeeper or servant then, by a single motion of the damper han- `dle 2Q not only controls all of the combustion passages, but sets'them in proper reletion to each other with the skill of a conibustion engineer. lY The illustrated arrangement of the rages, by which they all radiate from one location,venables all the various dampers to be condensed into a single moving part. This provides simplicity of constructionand ofy operation. It also makes possible the advantages illustrated in Fig. 3, which shows the position t-he parts may occup when coal is being added or ashes' remove The ter# minal vane 18 closes the inlet16 completely, thus shutting both the draft duct of the grate and the check draft of the Hue, while leaving the Hue 15 wide open for drawing gases,` line dust, etc., from the firebox into the iue. This position is attained by swinging the handle 20 as far as it will go to .the right; and it will be observed that in' the automatic control arrangement of Fig.` 1 the damper arm can under these circumstancesslide freely 'up on the rod 22; and may beheld in the extreme position as long as desired by a spring catch 20". i

The part 21 is shown hinged, for access to the interior for cleaning out soot, Any soot that may fall past the edges of damper 18 from the flue above will descend through the steepslope ofthe air draft duct to t-he ashpit. While the vane 18 is represented as a plane wing it.l will be understood thatit may be made of any suitable shape that will produce a change in size of opening, corresponding properly to the chan es inopenings to the Hue that result as tie vane 18 is moved. And in generalit may be said that changes in many respects may be madefr'om the precise structure here illustrated without departing from the scope of the invention.

l claim as my invention l. A draft regulator for furnaces compris'- ing the combination of a duct for draft of air to the under side of the grate; a duct from the upper side of the grate to the chimney flue, these ducts passing adjacent to each other; and a unitary damperV comprising a movable direct continuation of the Awall of each duct, located where the ducts are adjacent to each other, regulating both and preventing interchange of gases between them.

2. A draft regulator for furnaces comprising the combination of separate ducts for Iwhich air goes into the indraft of air and outdraft of products of combustion, passing in proXimlty to each other, and an L-shaped regulating damper having a vane projection into each duct.

8. A draft regulator for furnaces comprising the combination, with a duct for draft of air to the grate, a duct from the grate to the chimney and an air inlet adapted to be connected to each "duct, of a damper having interconnected vanes, one regulating the duct to the grate, another the duct to the chimney, and a third the air inlet, the whole arranged and adapted to open the passage from grate to the chimney progressively as the air draft to the grate opens, closing the air inlet connection to the chimney duct progressively during the first part of the motion and closing the air inlet Yduring the latter part of the motion. Y l,

4. A draft regulator for furnaces comprising a boX, containing passages through grate and the productsof combustion go out to thev chimney', combined with a damper pivoted within the box at thecorner between the said two passages, separating the said two passages so as to prevent inter ow of gases and regulating them simultaneously and similarly.

5. A draftregulator for furnaces comprising a box having anoutlet downward for draft of'air to the grate; an inlet on one side receiving discharge from the furnace; an inlet on the opposite side receiving air; and an outlet upward to the chimney; comhined with a damper pivoted between the first mentioned outlet and rst mentioned inlet, 4comprising onevane apportionlng the site lan inlet ont ie opposite side receiving air;

andan outlet upward to the'chimney; com- `bined with a damper pivoted between the first mentioned` outlet and first mentioned inlet; comprisinfr one vane apportioning the chimney connection between the inlets while the said vane is in an upper portion of its swing; closing the connection of chimney to air inlet while in a lower portion 'of its swing, and another vane Gradually opening the outlet to the grate as the first mentioned vane swings downward; and a third vane having a surface depending and gradually `bearing inward from the tip of the first mentioned vane, whereby the rate of change of air inlet connection to the chimney is moderated.

7. A draft regulator for furnaces com'- prising a boX having an outlet downward for draft of air to the grate; an inlet on one side receiving discharge from the furnace; an inlet on the opposite side receiving air; and an outlet upward to the chimney; combined with a damper pivoted between the first mentioned outlet and first mentioned inlet; comprising one vane apportioning the chimney connection' between the inlets while the said vane is in an upper portion of its swing; lclosing the connection of chimney to air inlet while in a lower portion of its swing, and another vane gradually opening the outlet to the grate as the first mentioned vane-swings downward; and a third vane having a surface depending and gradually bearing inward from the tip of the rst mentioned vane, whereby the rate of change of air inlet connection to the chimney is moderated, the depending vane being adapted to close said air inlet at its eXtreme swing, while the dischargeis wide open to chimney and the said vane controlling the outlet toV grate is wide open.

8. A draft regulator for furnaces comprising a box having an inlet for air and outlets for the air entering through said' inlet leading respectively to the grate and to the chimney; and an inlet from the grate; combined with a damper piveted within the box and having means to substantially close one of said inlets at each end of its movement and in intermediate positions to overn the flow of air through the two out ets.y

9. A draft regulator for furnaces comprising a box having an inlet for air and llltli t ian outlets for the air 'entering through ,said said outlet to the grate increasing it simulinlet leading respectively to the grate and taneously with increase of capacity of the to the chimney, and an inlet from the grate; inlet from the ate and with decrease of the combined with a damper pivoted Within the inlet to the chimney liue.

5 box and having means to substantially close Signed by me at Boston, Mass., this six- 15 the air inlet at one end of its movement and teenth day of October, 1912.

at the other end of its movement to sub- ARTHUR W. WALKER. stantially close Athe outlet to the grate and Witnesses: the inlet from the grate, and in its inter l EVERETT E. KENT,

10 mediate positions to vary the capacity of ANNA B. LINDSAY. 

